Filament support



06L 7, 1931. SUTHERLIN 1,829,423

FILAMENT SUPPORT Filed June 2, 1924 2. 9 l 'IH I1 I IIIHHUIE lWITNESSES: INVENTOR Patented Oct. 27, 1931 UNITED STATES PATENT OFFICELEE SUTHERLIN, OF EAST PITTSBURGH, PENNSYLVANIA, ASSIGNOR '10WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OFPENNSYLVANIA FILAMENT SUPPORT Application filed June 2, 1924. Serial No.717,391.

This invention relates to vacuum-tube de- Vices of the type used inconnection with radio reception, although it can be applied to othervacuum-tube devices as well.

It is an object of this invention to provide a means for yieldinglysupporting one end of the filament and supplemental means for dampingany movement of the filament.

This invention is an improvement upon the filament-supporting structureshown in the application of Hubert M. Freeman and Lee Sutherlin. SerialNo. 684,985, filed January 8, 1924, filament spring structures, assigned7 to Vestinghouse Electric and Manufacturing Company.

()ther objects of the invention and details of construction will beapparent from the following description and the accompanying drawings,in which Figure 1 is a- View in perspective, of a filament-supportingstructure embodying the invention,

Fig. 2 is a side elevation of the resilient friction member, and

Fig. 3 is a plan view of the same member.

Practically all vacuum-tube devices include an evacuated envelopecontaining various electrodes and a standard or standards for supportingthem. As the present invention is wholly in the structure connecting theend of the filament and the standard, the rest of the vacuum tube deviceis not illustrated.

The invention, although shown in connection with the upper end of thefilament, could equally well be applied to the lower end.

The standard 1 is of the usual form, consisting of an upright rod orwire, to the upper part of which is welded or otherwise secured aresilient wire or light spring 2. Near the end of this spring 2 farthestfrom the upright 1, is welded or otherwise secured, as shown at 3, theend piece 4: which constitutes part of the filament structure. Thefilament proper 5 is secured to the enlargement or end piece 4 in anyusual or desired way.

Preferably, the vacuum-tube device is assembled with the spring 2exerting sufficient force to keep the filament 5 under tension at alltimes, even though the filament expands upon heating. If preferred, themovement of the spring 2 may be made less than enough to completely takeup the expansion of the filament, leaving it slightly slack when hot.

Secured to the standard 1 below the spring 2 is a rigid arm 6.Preferably the arm 6 and the spring 2 are in the same plane althoughthis isnot absolutely necessary. The arm 6 is so positioned that itmakes contact with the end iece t.

A sprlng 7 is welded or otherwise secured to the standard 1 opposite thearm 6 as shown at 8.. Preferably, this spring is provided with an offsetor bowed portion 9. Beyond the bowed portion, the spring possesses astraight part 10 parallel to the arm 6. The straight part 10 of thespring engages the end piece 4 and presses it against the arm 6. The how9 gives to the spring 7 a sufficiently yielding character to make thefrictionbetween the end piece 4 and the arm 6 and the straight portion10 of the spring effective, even though slight inaccuracies in the formand location of theparts occur in manufacture.

When the vacuum tube containing this structure is jarred, the arm 6prevents the filament from moving in a plane at right angles to saidarm. The rigid connection be tween the end piece 4 and the spring 2prevents movement parallel to the arm 6. The filament and the end piece4 can, however,

move parallel to the standard 1 by vibration v of the spring 2. Whatevershock is received by the filament will, therefore, be translated into amotion in this direction.

When the filament is set into transverse vibration, there results ato-and-fro vibration of the end piece 4, because the tension thereon,due to the whipping action of the filament, varies periodically. Any jarof any kind is, therefore, translated to such a to-and fro movement ofthe end piece 4.

The pressure of the end 10 of the spring 7 against the end piece 4causes friction between the end piece and the spring and also betweenthe end piece and the arm 6. This friction rapidly dalnps the to-and-fromovement of the end piece, and so quickly stops any whipping action ofthe filament. Therefore, the only movement of the filament,

which any jar of any kind can give, is quickly I damped. No noise in thetelephone associated with the tube in the radio receiving set can,therefore, result from any jar of the tube.

Variations of the structure disclosed will readily occur to thoseskilled in the art. I, therefore, do not intend that vthe specificshowing of a single form of this structure shallbe construed as alimitation. No limitation except that required by the prior art andindicated by the claims is intended. Y

I claim as my invention: 1. In a filament support, a yieldable arm, afilamentend piece separating said arms and means resiliently acting I onsaid filament end piece to tension the filamentrr I i 2; In a filamentsupport, a standard, an arm secured to said standard, a filament endpiece, meansfor resiliently supporting said end piece, and a springsecured to said standard and yieldingly holding said filament end .piecein'frictional engagement with said arm.

3. In a filament support, a standard, an arm extending at an angle tosaid standard, a filament end piece, means for resiliently supportingsaid end piece, and means secured to said standard for holding saidfilament end piece in' frictional engagement with said arm.

4-. In a filament support, a filament end piece, aresilient supporttherefor, a standard,

an arm secured to one side'of the standard,

a spring secured on theopposite side of the standard and exertingpressure toward said arm, said filament end piece being positionedbetween, and in contact with, said arm an said spring. r In testimonywhereof, I have hereunto subscribed my name this 22nd day of May, 1924;i y r LEE SUTHERLIN.

